This may help you
First write and balance the equation, being:
CaCO3 - CaO + CO2
Then, using the periodic table, find the molecular masses of CaCO3 and of CaO, finding their ratio. That will be 100g:56g or 0.1kg:0.056kg. Since you have 4.7kg of CaCO3, it corresponds to Xkg of CaO. Making x the subject, it should be X= 4.7*0.056/100=0,002632
<span>N2 is a triple bond, N2H2 is a double bond, N2H4 is a single bond...the more electrons involved in the bond, the shorter the bond...therefore, a triple bond is the shortest and a single bond is the longest. Therefore N2H4 is the strongest.</span>
Transition metals are less reactive than alkali metals because of their high ionization potential and high melting point.
On moving from left to right of the periodic table for every period, electrons fill in the same shell or orbital, with the alkali metals having the least filled outermost shells, one electron, which equates to fewer protons in them.
Consequently, they have a lesser attraction power from the nucleus, whereas, the corresponding transition metals of the same period have more protons interacting with electrons at the same distance, far from the nucleus as the alkali metals.